The master thief Wang Wu wanted Da Hu, who possessed a part of a treasure map, to cooperate with You Xisheng and the Tao Feiyan couple in stealing the rest of the map from Diao Long, the leader of Qinglong Village. However, the couple were lured to Poison Dragon Valley by the Three Fiends of Changbai Mountain, and with the help of Master Yan, they obtained the Invincible Mandarin Duck Swords to fight off any oncoming threats.